The Miracle Fruit, a Tease for the Taste Buds - NYTimes.com: "The miracle fruit, Synsepalum dulcificum, is native to West Africa and has been known to Westerners since the 18th century. The cause of the reaction is a protein called miraculin, which binds with the taste buds and acts as a sweetness inducer when it comes in contact with acids, according to a scientist who has studied the fruit, Linda Bartoshuk at the University of Florida’s Center for Smell and Taste. Dr. Bartoshuk said she did not know of any dangers associated with eating miracle fruit.
During the 1970s, a ruling by the Food and Drug Administration dashed hopes that an extract of miraculin could be sold as a sugar substitute. In the absence of any plausible commercial application, the miracle fruit has acquired a bit of a cult following."